The present invention relates to displacement devices for controlled dispensing of a dose of a liquid contained in a cartridge, in particular for use for the infusion of medicine, such as insulin for diabetes patients, and comprising a housing incorporating a means for accommodating said cartridge, a manually activatable displaceable elongated dose dispensing means having a first end part extending to the exterior of the housing, an elongated piston rod connected with a displaceable piston, said piston being adapted to press out the liquid contained in said cartridge.
Such devices are well-known in the art, see eg. FR 2 572 288. Some of the known devices are cumbersome in use, and do not provide means allowing the user to readily verify that a preset dose is in fact dispensed. Other known devices do not permit resetting of the dose when this has been set, rendering the devices impracticable in use.